weight=80.5
height=1.75
BMI=weight/(height)**2
print('BMI')
if BMI<18.5:
    print('过轻')
elif BMI<25:
    print('正常')
elif BMI<28:
    print('过重')
elif BMI<32:
    print('肥胖')
else:
    print('严重肥胖')